• WordNet 3.6
    • v unfasten become undone or untied "The shoelaces unfastened"
    • v unfasten cause to become undone "unfasten your belt"
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Webster's Revised Unabridged Dictionary
    • v. t Unfasten To loose; to unfix; to unbind; to untie.
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Century Dictionary and Cyclopedia
    • unfasten To loose; unfix; unbind; untie; figuratively, to detach from any connecting link or agency; disconnect.
    • unfasten To come untied or unloosed.
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Chambers's Twentieth Century Dictionary
    • v.t Unfasten un-fas′n to loose, as from a fastening: to unfix. v.i. to become untied
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Webster's Revised Unabridged Dictionary
1st pref. un-, + fasten,


In literature:

One of her slippers had become unfastened, and the strip of lace had fallen from her head to her shoulders.
"Lourdes From the "Three Cities"" by Emile Zola
His prediction was verified a few moments later; the two ladies came in cheerfully, unfastening their fur cloaks.
"The Magnificent Ambersons" by Booth Tarkington
One of her slippers had become unfastened, and the strip of lace had fallen from her head to her shoulders.
"The Three Cities Trilogy, Complete Lourdes, Rome and Paris" by Emile Zola
Then with her slender fingers she tried to unfasten the knots that secured the cord.
"Henry Dunbar" by M. E. Braddon
Yet he unfastened his coats with a fine air of unconcern, and turned back his ruffles carefully.
"In the Valley" by Harold Frederic
I won't unfasten myself from you.
"Redemption and Two Other Plays" by Leo Tolstoy
In addition to this Haley tied his wrists together, fearing that otherwise he might be able to unfasten the knot.
"Brave and Bold" by Horatio Alger
Then she sank into a chair, and with trembling fingers unfastened her dress.
"The Strand Magazine: Volume VII, Issue 37. January, 1894." by Edited by George Newnes
When they had taken off his copper helmet and unfastened his canvas he leaned against the pump and breathed hard.
"Lister's Great Adventure" by Harold Bindloss
No door was left unfastened.
"The Atlantic Monthly, Volume 10, Number 60, October 1862" by Various

In poetry:

Then her wrath the mother cannot hold,
But unfastens straight the lock with ease
"In this house are girls become so bold,
As to seek e'en strangers' lusts to please?"
"The Bride Of Corinth" by Johann Wolfgang von Goethe
It nearer came, till it sunk at once
Close to his unfasten'd door,...
The stifled groan was a voice in death,
And he could count the ebbing breath,
Till his own would note no more !
"Basil" by Anne Bannerman
Yet should it unfasten itself and fall
Eddying down till it find your face
At some slight wind—-best chance of all!
Be your heart henceforth its dwelling-place
You trembled to forestall!
"By The Fire-Side" by Robert Browning
The apron of all inclement weather
Is roughly unfastened, there on high;
The apron of woes and misery
Is shaken by wind-gusts violently
Down on the hamlets that crouch together
Beneath the dull horizon-sky.
"The Snow" by Emile Verhaeren

In news:

Sebastien Loeb was given a two-minute penalty in Sardinia because his co-driver Daniel Elena unfastened his safety belts while their car was still in.
Unfastening one safety pin after another, I became more irritated by the second.

In science:

However, if the temperature is further increased ~m becomes progressively unfastened from the anisotropy and the transverse field competes mainly with the thermal agitation in aligning ~m; the response then exhibits a maximum and decreases as T is increased.
On the Statics and Dynamics of Magneto-Anisotropic Nanoparticles